Investigation of the Influence of Calcium Salts and Gelling Time on the Structural Mechanical Properties of Fruit Jam

Abstract
Alginate beads attract attention as a encapsulation matrix of bioactive substances in food. However, the stability of beads depends on calcium ion and sodium alginate concentration, gelling time and others factors. The aim of this study is to investigate the influence of different types of calcium salts on the structural and mechanical parameters - the rupture force and rupture deformation at different gelling times of the pear jam prepared with soluble dietary fibers and inulin. The relationships between the rupture force and rupture deformation of the fruit jams were established. By increasing the gelling time from 24 hours to 48 hours, the rupture deformation of jams with 7% calcium lactate were reduced and in those with 7% CaCl2 the rupture forces increases. Any change in rupture force was observed for the jam with 3.5% CaCl2. This study demonstrated the practical application of different calcium salts for preparation of stable pear jam.